Leads implanted in or about the heart have been used to reverse certain life threatening arrhythmia, or to stimulate contraction of the heart. Electrical energy is applied to the heart via the leads to return the heart to normal rhythm.
For example, one technique to apply therapy to the left atrium of the heart is to implant the electrode through the coronary sinus to reach a location below the left atrium. However, it can be difficult to locate the coronary sinus ostium, thus implantation time can be excessive, or the procedure can be unsuccessful. Also, some therapies require two or more electrodes located in separate chambers or locations within a heart. Typically, these electrodes are on different leads. However, implanting two or more leads within a heart increases the costs and difficulties of the procedure.